Denshi Jisho — Online Japanese dictionary

相 あい together; mutually; fellow
Prefix 
相 さが 1: one's nature; one's destiny;
2: custom; tradition; habit
Noun 
相 そう 1: appearance; look; countenance;
2: a 'seeming' that fortune-tellers relate to one's fortune;
3: (Linguistic term) aspect;
4: (Physics term) phase (e.g. solid, liquid and gaseous)
Noun 
相 しょう minister of state
Suffix 
相手 あいて 1: companion; partner; company;
2: other party; addressee;
3: opponent (sports, etc.)
Common word, Noun 
相撲 すもう 1: sumo wrestling;
2: (Abbreviation) sumo wrestler; rikishi
Common word, Noun 
相違 そうい difference; discrepancy; variation
Common word, Noun, Suru verb 
相互 そうご mutual; reciprocal
Common word, Noun, No-adjective 
相似 そうじ 1: resemblance; likeness; similitude;
2: (mathematical) similarity;
3: (biological) analogy
Common word, Noun, Na-adjective, Suru verb, No-adjective 
相場 そうば 1: market price;
2: speculation (e.g. on stocks);
3: reputation (according to conventional wisdom); estimation; esteem
Common word, Noun 
相子 あいこ draw; tie
Noun 
相図 あいず sign; signal
Noun, Suru verb 
相撲 すまい 1: sumo wrestling;
2: (Abbreviation) sumo wrestler; rikishi
Out-dated or obsolete kana, Noun 
相異 そうい difference; discrepancy; variation
Noun, Suru verb 
相思 そうし mutual affection or love
Noun 
相補 そうほ complement
Noun, No-adjective 
相 こもごも alternately; in succession
Adverb, Usually written using kana alone 
相対 あいたい confrontation; facing; between ourselves; no third party; tete-a-tete
Common word, Noun, Suru verb, No-adjective 
相槌 あいづち sounds given during a conversation to indicate comprehension; back-channeling
Common word, Noun, Linguistic term 
相棒 あいぼう partner; pal; accomplice
Common word, Noun 
相応 そうおう suitability; fitness
Common word, Na-adjective, Noun, No-adjective 
相関 そうかん correlation; interrelation
Common word, Noun, Suru verb 
相殺 そうさい offsetting each other; plus and minus equal zero; counterbalancing
Common word, Noun, Suru verb, No-adjective 
相続 そうぞく succession; inheritance
Common word, Noun, Suru verb 
相対 そうたい relative
Common word, Noun, Suru verb, Noun or verb acting prenominally 
相談 そうだん consultation; discussion
Common word, Noun, Suru verb 
相当 そうとう 1: befitting; becoming; worthy of; proportionate; in keeping with; suitable;
2: considerable; substantial;
3: (Suru verb) to be worthy of; to be proportionate to;
4: to correspond to (in meaning, function, etc.); to be equivalent;
5: (Adverb) extremely; considerably
Common word, Na-adjective, Adverbial noun, Suru verb 

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